Method of reducing and finishing wire



U ITED STATES PATENT ()rrice.

JAMES VVITHINGTON, OF GHAMBERSBURG, ASSIGNOR TO THE TRENTON IRON COMPANY, OF TRENTON, NEV JERSEY.

METHOD OF REDUCING AND FINISHING WIRE.

SPECIFICATION forming part of Letters Patent No. 3'7 .'7,000, dated January 24, 1888.

Application filed March 17, 1883. Serial No. 88,607. (No model.)

Be it known that 1, JAMES \VITHINGTON, a as to cause further additions of acid to lose citizen of the United States, residing in the their effect upon the rods, when the liquid is 55 borough of Ghambersburg, in the county of run off and replaced by fresh water and acid. 5 Mercer, and State of New Jersey, have in- When the scale has been sufficiently loosened vented certain Improvements in Reducing and by the acid, the rods are taken out of the Finishing WVire, of which the following is a tubs and either suddenlyimmersed in a tub of specification. r clear water or else subjected to a stream from 6c My invention relates to the manufacture of a hose (the more thorough as well as the more 1 annealed iron and steel wire, and it compreexpensive method) in order that. by washing, hends means whereby all operations of 'cleanall traces of scale and acid adhering to the suring are dispensed with excepting the first face may beremoved. Immediately after washcleaning of the rod. 'ing the rods are immersed in a bath of milk 65 As is well known, after wire has been drawn of lime, or other suitable coating material,and to a certain degree it becomes stiff and hard quickly dried, whereby a white coat is imand requires to be softened or annealed before parted to the rods which preserves them from it can be further drawh. For certain purposes rust. In some instances the lime is omitted,

also, wire, when finished, requires to be anbut this occurs only when the rods are to be 70 nealed, and is sold as annealed wire. It is tinned, coppered, or galvanized, or drawn 2 usuallycoated more or less with oxide scale or down into qualities of wire which do not resoot, and is distinguished from bright unanquire a bright finish. After coating with lime, nealed wire by its darker color and greater the wires are drawn or reduced in diameter pliability, ductility and softness. For certain by pulling through a series of holes or dies in 75 purposes again unannealed or stiff and elastic plates of cast steel or cast iron especially bright wire is in demand; while for yet other adapted for the purpose, the holes or dies bepurposes, notably that of making wire cloth, ing lubricated by any kind of grease, such' for in the weaving of which the scale upon dull or instance as tallow. This method of drawing I? blueannealed-wire t nds to cut out the reeds, wire through greased dies is technically known 80 annealed bright wire is called for. as the dry method, and its object is not only My invention aims to disclose a method to reduce the diameter of the wire but also to whereby bright annealed small size wire, a eff-ace the pits or marks caused by the eating product heretofore both costly and difficult of of the acidandrcnderthewirc perfectlysmooth To (1. whom, it may concern: i lution untilthe liquidbecomesso impregnated I l l production, can be cheaply made. upon its surface. 8 5

For the better understanding of my inven- Repeated operations of drawing, each time tion I regard it as essential to briefly state the to a smaller size, harden or stiffen the wire, present practice of wire making: making it more and more elastic, until a point A billet of highly heated iron or steel is first is reached when further drawing would de- I successively reduced through the gradually stroy the nature of the wire and cause it to 0 '-lesseningpasses of anysuitable rollingmill unbecome quite brittle. In drawing down to i" 0 til it emerges from the last pass as what is the finer sizes, therefore, it becomes essential known as a wire rod, the usual diameter of to soften the wire at certain sizes before it can I 'which is a little less than aquarter of an inch. be further drawn down. This is done by an p These wire rods are immediately and while hot nealing or heating to redness in suitable ves- 95 wound upon reels into coils. These coiled rods sels, the temperature depending upon the size 5 after cooling are next immersed in tubs 0011- of the wire, the larger sizes requiring the 'taining acid, preferably dilute sulphuric, or greatestheat. At predeterminedstages of the muriatic, to remove the scale or oxide,-suldrawing processes, therefore, or after the phuric acid permeating the coat of scale, looswires have been reduced to predetermined I00 ening it by attacking the iron itself, and comsizes, annealing must be resorted to, and subbiningwithit to form sulphate of iron or green sequent to each annealing the operation of copperas (or if muriatic acid is used chloride cleaning, washing, and 1ime-coating above of iron), which dissolves out and is held in sodescribed must be repeated. The sizes at which annealing is resorted to vary with different manufacturers and with the character of wire desired. The sizes known as Nos. 6, 9, 12, 15, and 18, are the sizes at which annealing is best resorted to.

After the wire has been reduced by the dry method to a size known as No. 18, it is impossible to proceed further with the method ofdry drawing, for thereason that such method in the finer sizes does not, by reason of the grease and lime employed, as herein fully eX- plained, meet the requirements necessary to produce a sufficiently smooth and bright surface, and what is known as the wet method must be resorted to for the making of wire of smaller sizes than No. 18.

The wet method of drawing, briefly stated, consists in first immersing wire,-after it has been reduced to the smallest size practicable by the dry method of drawing, and afterit has been in connection with said dry method of drawing annealed for thelast time and thoroughly cleaned by pickling,in a weak farinaceous glutinous or mucilaginous solution, such, for instance, as fermented rye flour, which forms upon its surface a mucilaginous film known among wire drawers as the lees coat;i'n then subjecting the wire with the lees coat upon it to the operation of being drawn down through a die; and in, finally, repeating the coating or immersion and the drawing down with a series of successively smaller dies. By this method only. has it been possible heretofore to draw iron or steel wire bright and perfectly clean. It has been inexpedient heretofore, however, to adopt the above method for the larger sizes of wire, by

reason of the fact that, after each annealing in the cast iron pots heretofore alone employed in connection with the said wet drawing prooes's, the wire, even when introduced in a clean and bright condition, has been taken out covered with scale and a dirty yellow or blue or dull black color, and this because of the gas generated in the pot notwithsta nd i ng the most complete exclusion of air possible,for which cause thorough cleaningin acid became necessary, after the cleansing off of which, immersion in water became also necessary instead of coating with lime, for the reason that the lime, being coarse, when mixed with the lees solution would cut out the dies and scratch the wire,'all of which steps necessitate more skillful labor and a more expensive plant and therefore increase the cost of the larger products over and above their cost by the dry process.

It is proper to remark thatin some instances, as in the case of harvester and broom wire which are completely finished at the size No. 20, the changefrom the dry to the wet method of drawing is effected at size N0. 15. \Vhatevenhowever, be the size at which the wire is for the last time annealed before being finished by the wet method of drawing, it is after the final annealing cleaned thoroughly by immersion,

bathing, or washing in acidulated liquor, and is then thrown into a bath of clear water until it is ready to be drawn. The office of keeping the wire in waterwhich must in thefirst place be perfectly free from acids or saltsis to prevent the rusting which would occur if the wire was exposed to the air for any length of time while wet from its immersion in acidnlated liquor, and also to dissolve out any traces of acidulated liquor that may remain in the wire. The water in the wet method, therefore, subserves the same purpose that the lime coat does in the dry method. In the fine sizes of wire, however, the strands lie so closely together in the hank that the operation of cleaning in acidulated liquor becomes a very laborious one, and it becomes necessary in order to to move the adhering particles of scale, after the coil or hank has been removed from theacidulated liquor, to loosen the fastenings ofthe coil, spread out its strands, and resort to what is known as batting, a most lengthy and laborious operation. it is impracticable therefore to clean sizes finer than No. 18, so that it is absolutely necessary in the drawing down on these sizes that the surface of the wire should be kept perfectly clean and smooth. This condition also compels the operation of annealing of the sizes below No. 18 to be dispensed with, excepting of course such annealing as is resorted to with small wire which has broken or fallen out in the drawing before reaching its intended ultimate diameter, and which fits it to be sold as annealed fine wire, a product frequently disposed of below cost, because the falling outfrequently happens at sizes for which there is no demand.

After the wire has been properly cleaned upon its final reduction by the dry method at No. 15 or No. 18 as the case maybe, and when it is not essential that the ultimate product should be silver or liquor bright as it is termed, the wire, before being subjected to the wet drawing process, is lacquered or dipped for a few seconds in a weak solution of a salt of cop per, such, forinstance, as the sulphate of copper, which deposits a film of metallic copper on its surface that serves not only to protect said surface from rust but also to assist the lees-coat in lubricating the dies through which the wireis subsequently drawn. 'lhelacquered wire is next immersed in a tub of lees from which it is continuously drawn, according to the wet method, through a die. This operation of immersing in lees and drawing through a die is repeated through a series of dies each smaller than its predecessor until the final re duction is attained. The lacquering may also, in connection with the above operations, be either occasionally repeated or may, ifdesi red, be repeated before each drawing, provided however, as already stated, a silver or liquor bright finish be not desired,for the reason that, while the lacquer greatly assists the lubrication of the dies and is therefore advantageously employed, it yet, when once applied, adheres ffO ' stififening very fine sizes (from No. 26 to No. 36)

would be avoided, but it is obvious that beso when charged with wire would leave but a tent.

the excessive labor in batting, there would ble extent the oxidation, but yet not to such so closely to the wire that it affects its ultimate tint and, while not affecting its brightness, imparts to it a distinct reddish cast.

Throughout the entire conduct of the above Web drawing or reducing process, it has, for reasons already fully stated, been impracticable' to anneal the wire; and the result has therefore been that, although the percentage of each reduction has been comparatively small, yet the tensile strain on the gradually has been so great that only the very best material endures to the ultimate reduction, and much even of the very best material in the best practice falls out as it is technically called, or breaks in the drawing before reaching the ultimate size. This wire has heretofore, therefore, been annealed and disposed of at a sacrifice. Of course if it were practicable to clean fine wire this difficulty tween the oxidation in the operation of annealing and the consumption ,of iron by the acid in the operation of cleaning, to say nothing of not be sufficient substance of wire left to pay for the cost of drawing.

Having now described the usual operations of manufacturing the various sizes of wire, it is proper for me to add that heretofore for many yearsit has been a desideratum with manufacturers of wire to anneal in such a manner that after the annealing process the wire could be immediately drawn without being first subjected to thelaborious and expensive operation of cleaning, or pickling, heretofore described. Two serious conditions or obstacles however have heretofore existed to prevent,viz: the formation of scale upon the metal and the depositof soot. The formation of scale results from the oxidation occurring when the wire is heated to redness in contact with air. The film of soot is produced by the carb onization of greaseexisting upon all bright wires drawn by the dry method and more especially upon the larger sizes. Many experiments to prevent the formation of the light scale of iron oxide have been made, such, for instance, as the construction of pots which minimum air space, such space being filled with sand, roll scale, mineral wool, asbestus, and various refractory substances, the result of which has been to decrease to an appreciaan extent as to enable the operation of cleaning to be altogether dispensed with or to permit of a commercial adoption to any great exl The film of soot is even more difficult to remove than the scale as it is unaffected by acids, and must, especially on the finer sizes of wires, be manually removed by washing with'water and by the operation of batting. It is'by reason of the formation of scale and deposit of soot also that the dry method of drawing wire is inapplicable for the finer sizes which are therefore drawn by the wet method as'heretofore explained.

Having now not only described the operations usual and heretofore necessary for the manufacture of the various sizes of wire, but also fully explained why, although desirable, it has been heretofore impossible to anneal wires so bright and clean as to avoid subsequent cleaning processes-it is proper for me to state'that my invention comprehends the production or discovery not only of a method of making bright annealed wires of the various larger sizes without having recourse to any other process of cleaning than that employed to clean the rods from which said wires are subsequently drawn,but also a process or method of making the finest sizes ofbright annealed wires, or those below the diameter of No. 18, without either the loss of great quantities of the same by breakage or falling out in v the drawing before the ultimate size is reached, or without dulling their surface or destroying that brightness which is essential to make these smaller varieties of the highest com mercial value. I

I have discovered that the foregoing desirable conditions can be fulfilled and results secured in the following manner, to wit:-

I first take the rod which has been rolled from the billet, and pickle and cleanse it in the manner hereinbefore described. I then coat the cleansed product by means ofa farinaceous, glutinous, or mucilaginous solution, such for instance as a weak solution of rye flour, and such as is known as a lees solution because forming upon the surface of the wire a mucilaginous film known among wire-drawers as the lees coat,and draw the coated product through a die, not only to reduce its diameter but also to smooth its surface and efface the acid pits. If the ultimate product is not to be silver or liquor bright but simply bright, I preferably not only at this stage but subsequently from time totime as the lacquer wears off resort to lacquer-ing in connection with the lees coating. The lacquer-ing, however,is not essential. I then repeat the coating and drawing through a smaller die as frequently as may be necessary or desirable and until the wire requires to be annealed. I then seal the wire in its thoroughly cleansed condition and in such sufficient quantity to as nearly as possible fill the pot,in tightpots or vessels of sheet or tank metal, boiler or armor plate, being preferably wrought iron although they may be of steel, and subject the wire so contained or inclosed to the action of heat in order to anneal it. When the process of annealing is completed and the pots and contents have cooled, I then remove the annealed wire from the vessel in which it has been annealed, and find that said wire is clean and as brightas it was before being annealed. I then again subject the clean and bright annealed wire to the lees solution (either with or without lacqueriug) in order to coat it, and draw the clean coated product ICO through a die, all in the manner above set forth, and subsequently repeat both the immersion in a lees solution and the drawing through a die as frequently as maybe desired, in order, by aseries of gradually smaller dies, to draw the wire down from the size at which the operation is commenced to the ultimate diameter desired.

In connection with the above wet-coating and drawing down, the operation, above described, of annealingin wrought iron or steel is usually to be repeated three or four times before the size No. 18 is reached, and at no stage of the operation is pickling, inseparable from the dry drawing process, necessary.

After the last annealing in wrought iron resorted to at or before size No. 18, and when a very small size of bright annealed wire, known as stone wire, is theproducthadin view, the wire is subj ected to repeated lees coatings (and, if the silver or liquor bright finish be not (le sired, lacquerings) and to repeated drawings, each time through a smaller die, until the at timate desired diameter is reached. With the very best stock the above operation, such is the virtue of annealing a clean product in wrought iron, is possible without other an nealings than such as are resorted to before the size No. 18 is reached, but with some mar terial, which a skilled workman will readily recognize, it becomes necessary to repeat the operation of annealing in wrought iron once, and in exceptional cases several times, between the size No. 18 and the ultimate size; this annealing is however readily performed without any process of cleaning, for the reason that the wire being clean and bright when it is put in the annealing vessel comes out of it clean and bright, as hereinbefore fully explained.

It is manifest that the wet method of d rawing, or drawing by the aid of a lees coat, is the only one applicable in the process which I have discovered, practiced, and above described, as it is essential that the wire when put in the annealing pot should be perfectly clean in, order that it may be taken out in the same condition, and as it is impossible either to draw wire after the method of dry drawing with grease, the surface of which is in the slightest degree coated with scale, soot, or dirt, without soon cutting out the dies, or to anneal it bright even in wrought iron without first subjecting it to thorough cleansing.

The wrought iron annealing pots which I employ in connection with the above process, having been filled with wire, are in the prac tice of that process placed in-an annealing furnace preferably provided with a cast iron receptacle or chamber adapted to receive them and to prevent their coming into direct contact with the flame of the fires. After being heated to the required temperature they are taken out and allowed to become perfectly cold before they are opened and the wire re moved and subjected to the subsequent drawings. I have said that the pots may be composed of steel as well as of wroughtiron, and this is by reason of the fact that steel can be made so low in carbon thatthereis chemically no difference between it and some grades of wrought iron, the distinction between the natures of steel and iron being now admitted to be merelya molecular one produced by their different modes of manufacture.

By the above method of annealing brightin wrought iron pots, and in connection therewith of drawing the bright annealed wires when coated with the lees -coat through dies, I am enabled to entirely dispense with all the operations of cleaning except the first cleaning of the rod, and also to dispense with thehithcrto objectionable method of dry drawing by the aid of grease, and to employ the wet or lees-coat drawing with the sizes above as well as with those below No. 18. I am also able, when it becomes necessary to anneal below size No. 18, to anneal bright and, without cleaning, by the aid of the leescoat draw to any degree of fineness the sizes under the said No.18, and to thus certainly even with poor stock produce those sizes which have hitherto been ditficnlt to manufacture because the wire drawn down to make them has frequently hitherto broken or fallen out before reaching the said ultimate sizes, and I produce moreover a softer and superior quality of wire than that heretofore made and which has not required such annealing.

By the practice, therefore, of this invention, I am enabled to utilize a large quantity of wire heretofore broken or fallen out in the proccss of drawing down, and which has horeto fore therefore of necessity been annealed and disposed of at a sacrifice as dull or blued aunealed fine-size or stone wire, and in this particular I effect a material saving which in large wire mills will amount to many thousands of dollars in a year.

It will of course be readily understood that many solutions other than that of fermented rye flour may be resorted to in order to provide the surface of the wire with a mucilaginous film or coating of lubricating material adapted to facilitate the operation of drawing through dies, and it is proper for me to state that I do not restrict myself to any special solution or coating, although fermented rye flour is perhaps preferable. 1', also, do not lay stress upon any specific form or construction of annealing pot, or furnace within which to heat such pot, as many forms and constructions can be profitably employed, and as the gist of the thing so far as the annealingis concerned resides in the employment of wrought iron per se for the inclosing of wire, andin the subjecting of it so iucloscd to heat necessary to anneal it.

I am aware that I am not the first to employ wrought iron vessels in which to conduct operations of annealing, where the product to be annealed was both introduced and removed from the annealing vessel in a dull, dirty, deposited, or artificially coated condition, but,

so far as my knowledge extends, I am the first to have discovered that when thoroughly cleaned or bright metal products are introduced into a wrought iron annealing vessel in quantities'sufficient to completely fill it they can be removed therefrom in the same bright 'andclean condition 'in which they existed when introduced. This discovery I do not, however, claim in this application (and its consideration per se is not pertinent here) as it constitutes the subject matter of another appli'cation of mine now pending in the Patent Office. It is also proper for me to explain that I lay no claim to the invention of the process known as the wet drawing process, or a process consisting of the drawing down of a wire through a die when the wire has been previously coated with a farinaceous, glutinous, or mucilaginous film or coat, as this process in connection with the employment of cast iron annealing pots has been, as herein previously explained, long in use, but

What I do claim and desire to secure by Letters Patent is:- V Y 1. The method of finishing wire hereinbefore described, which consists: first, in subjecting cleansed wire rods or annealed wire contained or inclosed in a wrought iron or steel vessel to the action of heat in order to anneal it bright; second, in coating the bright annealed wire,"after it has been cooled in and then removed from the annealing vessel and without any intermediate operation of pickling or cleaning, with a farinaceous, glutinous,

or mucilaginous solution; third, in drawing the coated bright annealed wire through a die;

second, in coating the cleansed product with a farinaceous glutinous or mucilaginous solution and in drawing the coated product through a die; third, in subjecting the cleansed and drawn product contained or inclosed in a wrought iron or steel vessel to the action of heat in order to anneal it bright; fourth, in coating the bright annealed wire after it has been cooled in the closed annealing vessel and removed therefrom, and without any intermediate operation of pickling or cleaning, with a farinaceous glutinous or mucilaginous solution, andin drawing the coated bright annealed wire through a die; and, fifth, in repeating the above named steps'of coating and drawing (and if required of annealing) until the ultimate desired diameter of wire is reached, all substantially as hereinbefore described.

In testimony whereof I have hereunto signed my name this 12th day of March, A. D. 1883.

JAMES W'ITHINGTON.

In presence of J. Bo'NsALL TAYLOR, W. O. STRAWBRIDGE. 

